Climate Change and Wildlife

How a Changing Climate is Impacting the World’s Wild Animals – and Plants, Too

By: Ben Callison

Contrary to what skeptics may think, climate change is no longer something to be debated. We’re witnessing its effects all over the planet in real time, and they’re taking a devastating toll on wildlife and habitat. The numbers don’t lie – 16 of the 17 warmest years on record have occurred since 2000, altering the start time of spring and forcing species to shift their ranges.

The sea level rise over the last decade was twice what occurred over the last century, threatening nesting sites of loggerhead sea turtles and piping plovers. And sea ice is now absent when polar bears emerging from winter dens need it for hunting to feed themselves and their cubs.

A recent study of mammal and bird species on the IUCN Red List of Threatened Species reveals the harmful effects of climate change are occurring even more quickly than climate scientists anticipated. Nearly half of the mammals and nearly a quarter of the birds studied already show signs of being impacted by climate change. As more than 97 percent of climate scientists have said for years, climate change is happening, and human activities are a significant cause. Action is our only option. Wild animals validate this fact as they strive to adapt to harsh and sudden changes.

In 2008, polar bears became the first species protected under the Endangered Species Act specifically due to projected impacts from climate change. Nine years later, we have still not taken sufficient actions to save the sea ice that would spare this bear from almost certain extinction.

The impacts on many other species also demonstrate the need for urgent action to slow the pace of rising greenhouse gas emissions. Retreating springtime snow cover in the northern Cascades and the Rocky Mountains is fragmenting wolverine habitat. Snowshoe hares are increasingly vulnerable to predators, as seasonal changes in their fur color no longer synchronize with the timing of snow cover. American pikas – an alpine species needing moist, cool habitat in summer and snow for insulation in winter – have disappeared from much of their range, as suitable conditions are now found only at higher elevations.

Arrival times of migratory birds evolved to synchronize food abundance with hungry nestlings, but wood warblers and others now arrive too late for the peak of caterpillars to feed their young. Some bird species are forced into marginal habitat when changes occur in weather conditions and vegetation. Longer, more intense droughts caused by climate change lead to wildfires that destroy sagebrush habitat that sage grouse, sage thrashers, and sage sparrows need.

Plants Are Suffering, Too

The life cycles of plants and insects are also changing and disrupting wildlife. Warmer, drier conditions early in the growing season are shifting blooming times, disrupting flower-pollinator relationships. Drought and altered frequency and intensity of fires have contributed to increases in insect pests, causing some western forests to experience up to 87 percent mortality of conifers, which imperils wildlife dependent upon them. Milder winters in the moose’s range are contributing to exploding numbers of ticks, a parasite that can gather in the thousands on a single animal, sometimes causing death.

Most vulnerable to the impacts of climate change, perhaps, are amphibians. About one third are already at risk of extinction due to habitat loss and other threats. Climate change is a formidable threat to their life cycle in multiple ways. It disrupts needed predictability of water availability, inundates freshwater habitat via storm surge or sea level rise, and causes radical temperature shifts at delicate times of transition.

We Need to Act Now

As reckless architects of the chaotic changes impacting life all around us, we have a duty to become architects of effective mitigations. Scientists tell us the best way to do that is to protect as much habitat as we can, improve connectivity among lands and restore habitat wherever possible. These are tangible, practical ways we can – and must – help wildlife survive the impacts of climate change. Wild animals need options and the ability to safely reach them. Their struggles and losses are real. It’s up to each of us who care to help wildlife find a viable path forward.

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